package iedcyt.acute.utils;

import java.io.IOException;
import java.net.URL;
import java.net.URLConnection;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.StringTokenizer;


public class CookieHandler {

private Map repository;

private static final String SET_COOKIE = "Set-Cookie";
private static final String COOKIE_VALUE_DELIMITER = ";";
private static final String PATH = "path";
private static final String EXPIRES = "expires";
private static final String DATE_FORMAT = "EEE, dd-MMM-yyyy hh:mm:ss z";
private static final String SET_COOKIE_SEPARATOR="; ";
private static final String COOKIE = "Cookie";

private static final char NAME_VALUE_SEPARATOR = '=';
private static final char DOT = '.';

private DateFormat dateFormat;

public CookieHandler() {
repository = new HashMap();
dateFormat = new SimpleDateFormat(DATE_FORMAT);
}

/**
* Retrieves and cookies stored in repository
* @param conn a opend URLConnection
* @throws java.io.IOException Thrown if conn is not open.
*/
public void storeCookies(URLConnection conn) throws IOException {
String domain = getDomainFromHost(conn.getURL().getHost());
Map domainStore;
if (repository.containsKey(domain)) {
domainStore = (Map)repository.get(domain);
} else {
domainStore = new HashMap();
repository.put(domain, domainStore);
}

String headerName=null;
for (int i=1; (headerName = conn.getHeaderFieldKey(i)) != null; i++) {
if (headerName.equalsIgnoreCase(SET_COOKIE)) {
Map cookie = new HashMap();
StringTokenizer st = new StringTokenizer(conn.getHeaderField(i), COOKIE_VALUE_DELIMITER);

if (st.hasMoreTokens()) {
String token = st.nextToken();
String name = token.substring(0, token.indexOf(NAME_VALUE_SEPARATOR));
String value = token.substring(token.indexOf(NAME_VALUE_SEPARATOR) + 1, token.length());
domainStore.put(name, cookie);
cookie.put(name, value);
}

while (st.hasMoreTokens()) {
String token = st.nextToken();
cookie.put(token.substring(0, token.indexOf(NAME_VALUE_SEPARATOR)).toLowerCase(), token.substring(token.indexOf(NAME_VALUE_SEPARATOR) + 1, token.length()));
}
}
}
}
/**
* Prior to opening a URLConnection, calling this method will set all
* unexpired cookies that match the path or subpaths for thi underlying URL
*
* The connection MUST NOT have been opened
* method or an IOException will be thrown.
*
* @param conn a java.net.URLConnection - must NOT be open, or IOException will be thrown
* @throws java.io.IOException Thrown if conn has already been opened.
*/
public URLConnection setCookies(URLConnection conn) throws IOException {
URL url = conn.getURL();
String domain = getDomainFromHost(url.getHost());
String path = url.getPath();

Map domainStore = (Map)repository.get(domain);
if (domainStore == null) return null;
StringBuffer cookieStringBuffer = new StringBuffer();

Iterator cookieNames = domainStore.keySet().iterator();
while(cookieNames.hasNext()) {
String cookieName = (String)cookieNames.next();
Map cookie = (Map)domainStore.get(cookieName);
if (comparePaths((String)cookie.get(PATH), path) && isNotExpired((String)cookie.get(EXPIRES))) {
cookieStringBuffer.append(cookieName);
cookieStringBuffer.append("=");
cookieStringBuffer.append((String)cookie.get(cookieName));
if (cookieNames.hasNext()) cookieStringBuffer.append(SET_COOKIE_SEPARATOR);
}
}
try {
conn.setRequestProperty(COOKIE, cookieStringBuffer.toString());
} catch (java.lang.IllegalStateException ise) {
IOException ioe = new IOException("Illegal State! Cookies cannot be set on a URLConnection that is already connected. Only call setCookies(java.net.URLConnection) AFTER calling java.net.URLConnection.connect().");
throw ioe;
}
return conn;
}

private String getDomainFromHost(String host) {
if (host.indexOf(DOT) != host.lastIndexOf(DOT)) {
return host.substring(host.indexOf(DOT) + 1);
} else {
return host;
}
}

private boolean isNotExpired(String cookieExpires) {
if (cookieExpires == null)
return true;
Date now = new Date();
try {
return (now.compareTo(dateFormat.parse(cookieExpires))) <= 0; } catch (java.text.ParseException pe) {
pe.printStackTrace(); return false;
}
}

private boolean comparePaths(String cookiePath, String targetPath) {
if (cookiePath == null) {
return true;
}
else if (cookiePath.equals("/")) {
return true;
}
else if (targetPath.regionMatches(0, cookiePath, 0, cookiePath.length())) {
return true;
}
else {
return false;
}
}
}
